The process of decaffeination in coffee beans in the past has either involved the use of chemical products such as methylene chloride, or the more common method os Swiss Water osmosis processing. Specialty coffee roasters like ourselves have always favoured the Swiss Water approach as the product is not only of higher quality, but also doesn't involve any nasty chemicals.
However, a new process has been developed which sees the use of the natural chemical, carbon dioxide (CO2) used to extract the caffeine from green beans and has proved to retain more structure and flavour than the water processing of the past. This process has been patented by CR3 as the, 'Natural Liquid Carbon Dioxide Decaffeination Process' - or CO2 process for short.
CR3 uses carbon dioxide to extract 99.9% of the caffeine from coffee. In order to do this, first the green beans need to be moistened with water, before being placed into a vessel whereby they are brought into contact with pressurised, liquid carbon dioxide. The CO2 picks up the caffeine in the beans and takes it out the vessel and into an evaporator. Once the caffeine has precipitated from the beans, the CO2 can be reintroduced to the coffee. The process is repeated until the caffeine residual level reaches 0.01%.
The particular parameters in which the beans are processed guarantees a high retention rate of the coffee components that are responsible for both aroma and taste. The beans are then discharged into a dryer where they are gently dried until they reach their original moisture content. It is then that the decaffeinated coffee is ready to be roasted - pretty cool, hey?